Method of and apparatus for fining glass



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1 R. D.- PIKE METHOD 0F ANDAPPARATU FOR'FIN'ING GLASS Filed Nov. 1, 1922 2 sheets-sheetA '2 l L INVENTOR.

.Page f Patented Aug. 3l, 1926.,

renti ROBERT D. .PLKE, OF SAN FRANCISCO, CALIFORNIA, ASSIGNR TO Cillzl-FRENCH @will rANY; A CORPORATION.

METHOD OF AND APPARATUS FOR FHQ'KNG GLASS.

Application l'ed November 1, 1922.

This invention relates to fining of glass; and has for its object to facilitate the removal of gaseous products of decomposition and other volatile impurities. This object I accomplish by the employment of vacuum or suction acting upon the melted glass, either Within the furnace or Within a separate ning compartment.

Oneform which my invention may as- ,sume 1s exemplified in the :following description and illustrated in the accompanyingr drawings, in which-- ig. 1 shows a plan view of an apparatus embodyin my invention.

-lIig. 2s oWs a vertical, central, sectionpl View. y' v Fig. 3 shows a vertical, central, sectional View of a vacuum chamber-,fitted with electrical heating means.

Fig. 4 shows a cross section of the same, taken on the line 4 4 of Fig. 3. p

Fig. 5 shows a cross sectional View, teken on the line 5--5 of Fig. 3.

The glass leaving the melting furnace l flows through the submerged port Ginto -o compartment 18 having a root' 18 with a central hole 18h.' Through the hole 18h projects aisuction pipe 19, composed of gas tight steel sheeting 20 and lined on the inside with refractory' and insulating material 21, faced with a dense porcelaindike lining 2l.

At the lower end or" the suction pipe is a Water jacket 22 with asupply pipe 23 and outlet pipes 23". The outer surface of the Water jacket is protected by refractory and insulating lining 21 and a porcelain-like lining 21. The pipe 19 is dipped into the lass until the glass level 5 is a little above t e level'oi the bottom of the Water jacket 22. The upper end of the pipe 19 terminates in a vacuum chamber 24, which is also lined with refractory and insulating lining 21 and porcelain lining 21 and is connected through a pipe 25 to any suitable source of vacuum. The Word vacuum is used relatively, the pressure being automatically retainedV atsuch' a point that the glass holds a more or lesspermanent .level 5 Within the vacuum chamber 24. lt will be understood that the reduced pressure in 24 causes the molten glass to rise in the pipe 19 and.

artly lill the chamber 24, It the vacuum 1n chamber 24; be. practically perfect, the

' scende into the Working compartment Serial No. 5913,2@5

. his results in a flow downwardly through lftdand e corresponding dow upwardly through 19. But as the glass passes up through pipe ligand through vacuum chamberffl, the reduced pressurev causes it to give up e. large portion of its dissolved and absorbed gases', so that when the glass de- 16 it is lined and. fread for Working.. 'l 7 lin phssing through the vacuum compartment 24 and the pipes 19 end lil, there will be a certain loss of temperature in the glass. This may be eounteracted in any suitble fashion, ris-for example, lby the rossore I use ofinsulating brick 21 between the refractory porcelain-like lining 2l and the steel shell 20;`by heatingr the glass hy any suitable means in passing through the chamber Q4; or hy heating the glass by any suitable means While in the Working com partment l.

The entire -vacuum compartment can be lifted by crane and replaced by a, new one, should the lining Wear out or for any other reason. Before placing 'fresh vacuum up paratus'in place, it should be heated internally to the approximate temperature of the glass. This can be done by tiring fuel into it through either one of the pipes 19 or 19a., or through any other suit-able opening.

A method ot heating the glass electrically While passing through the vacuum is shown ,in Figs. 3 to 5, inclusive. For this pur' oso y n later .Whether eleioalfheating be employed or not, to open up thejapparatne and permit of lll@ ree

pleeing er rethe lining. The letter is lielfl tiem' :f in 'place ie the respective lielvee by the ilanges 3?'.

le practice, the porcelain lining 2l een he cest in place b 1L Well keiewn meilieiis; me then dried an tired in piece by eiectricel heat; the part of the lining 'tie tower heit of 24: being heated by the electrical resistor in the upper half 'amel the liriing in tile pipes 19 and lQ being heeteii lijf; specie electrical resistors provided :tor'tlie impose, By this means en exceedingly,

ureblfe lining, free 'from icilets, ceri be re- .A vided, and at the same time-excessive neet U4 ably mede ei e highly retrectcry :gi-n highly liest emiduetive substance, es, for exemple, megnesite liriclrs, and is seperated trein the steelshell ein its upper 'face by the retiree tory and insulating lining 35. The electricel current, usually elternetiugg, is cctv ducted to the carbon resister 'thrciigjli the graphite electrodes 36.

t is necessary to conduct the eleetrieel current .through the-steel shell 2G :Witheet coming into electricel eontect vfiti seme mullet the seme time proviing en airtight joint. This may lee accemplislied try the following means:

A steel pad 37 is weitleti om te the steel shell 20, cnil e threaded hole tcppecl through, into which is screwerl the bushing S8. lnto this is fitted the pcrecleii bushlig 39, which rests on. shoulder et the lower extremity ci? the bushing 38 and is prefer ably cemented into place. The copper tube fhtwing a seelecl` and threaded lower extremity, passes through the bushing 39, emi

- the copper shoulder il rests in ely recess 42 und ie separated from the porcelain by airtight gasket 43. The copper tube 40 is screwed into a, threaded hole in the graphite 4electrcle 367 tlius making an electrical connection with the latter.

A special shaped gasket er packing' ai rests on tcp of the ring 41 and the bushing 39, ami on top of this letter pecking reste the porcelain bushing 45; the latter being; screwed up tight by the gland 4,6. Electrical lend Wire is attached to the tube Il() by clamps 8. A brass litting i9 lies screwed into it e, copper tube 50, commmiceting with e passage which, in turn, communicates with afweter supply funnei 52. 'When the fitting 4t? is seieweL into piece, the lower? end et the ifelse 5U cle-se te the eefaled bottom of the tube el). The tting 49 1s also supplied with eiitlet duct is e result et this arrangement, wat

peered inte iiinel 52 circulates through tlic cappe? 4G@ keeping' tlic seme cool emi discharging tl-eugh any suitable pipe 54,

It is. time eeen that the above described erraegeiiient previflee for the passage ci en electricel current inte the interim: cf e chamber Qi Witheet destroyingthe mecum which is; meinteitied therein7 cnil which eci"- Y-entpassing through the .granular carbon resister lieete seme, which liet is C'- ferred by redieticii end cenducticii through 'ehetl reci? 34C te the glass which is in the process ci: being fined.

B37 virtue ci? this arrangement :mil lay meinteining the glass in the vessel 3 8 suitebiy elevated temperature, there will never lce eey enger o tile glass', which.

icevs through the vacuole liner, ieeccming coeler than e certain prescribed limit, eet ley the eiicimt et current passing through the cer-bcn resister7 and this willv liclil izflietlier much cr little glass is flowing tlireugii the iier.

By e empleymeitci' e retlueecl pressure or veceure, the @ning et the glass is ffreetiy ecilitete. The Vacuum removes not only the gases of ciecemposition but other vvolatile impurities emi en); issolved or edserbefl geses7 time producing e glass ci grelt semiclziese etici The meezirium eect el the vacuum is ley subjecting the molten glass to ite e .eii for et leest erle-heli hour, emi by applying vecuum gradually. 1 eccemplisi'. the former by making the vacuum. chamber ci2 impar size, so that the' glass remains therein et leest ene-heli heur; and the letter is inherent in my apparatus itiesmucli es lie vacuum is applied gradually te the gleee es it Eews upwardly through' the sucticri pipe inte the vacuum cliember.

Various cli-enges in the 'construction met arrangement of the several parte herein shown may loe employed without rleperting from the spirit et my invention as clair-lect claim:

L t mettrocl of timing glass, which celisists in passing the melted glass tiirtmgh e vacuum cifxeiiiloer enc eppiyiig Seiall chalutier to ziiairiteiu tire temperature or the glass 2. metlioi of iiing gilles, which consiste in passing tlie meltecl glass through vacuum ehemlJer anni heating the cheminer electrically.

3. rllie cornloiiietion with e gless tenir furnace, ci e 'vacum chamber connecte@ therewith ei'i tiireugh which 'the glass is passed for tlie pilrpcse cf filling, enel, electrieel beating means. te maintain tempemtlire lll' l working chem lessees ci' alle glass While passing?- through said chamber. V The eombination with a glass tank furaael a workin# chamber, of a vacuum chamber arran ed etvveen, the furnace and er and through which the ,f5-'lass if; passed to subject it to a ining action,

and electrical heating means arranged.

within .said vacuum 'chamber to maintain the temperature of the glass.

5. In combination with a glass tank furnace, a ning device for glass comprising a vacuum chamber arranged above the level of the glass, a pipe leading from the furnace into one end of said chamber, a Working chamber connected with the opposite end of the vacuum chamber, and electrical heating means arranged within said vacuum chamber to maintain the temperature of the glass.

ROBERT l). PIKE. 

